Select all records don't meet certain conditions in a joined table

Question

Let\'s say we have two tables here , posts and comments, the relations is one to many, there has a field call comment_date in the comments table.

Now I am struggle t

Answer 1

SELECT  *
FROM    posts
WHERE   post_id NOT IN 
        (
        SELECT  comment_post
        FROM    comments
        WHERE   comment_date >= @deadline
        )